vitreous for undergraduates

1. TOPIC:VITREOUS
DR SAKSHI SAHNI
ASST PROF
DEPTT OF OPHTHALMOLOGY
ASCOMS

4.  Functions :
 Serves mainly optical functions
 Mechanically stabilises the eyeball
 Pathway for nutrients to reach the lens and
retina.

5. Embryology :
 vitreous body Derived from neuroectoderm
of optic disc.
 During stages of development ,secondary
vitreous fills the cavity , primary vitreous
along with hyaloid vessels is pushed
anteriorly and ultimately disappears.
 Tertiary vitreous is developed from
neuroectoderm in the ciliary region and is
represented by the ciliary zonules.

7.  Vitreous base : part of the vitreous 4mm
across ora serrata.
 It is the strongest attachment.
 Anterior face of the vitreous cortex is
attached to the posterior surface of the lens

9.  In rest of the retina , vitreous cortex is loosely
attached to the ILM being comparatively less
loose along the major retinal vessels

12.  Vitreous opacities
 Extremely annoying as they cast a shadow on
the retina and
 Appear as black spot moving in and out ofVF
 Patient complains of moving flies or insects
infront of eyes
 Pathologically these are clumped cells or
strands of vitreous gel which become less
transparent than rest of the vitreous

13. VITREOUS OPACITIES :
 Developmental opacities:
 Located in the canal of cloquet
 Are remnants of hyaloid system
 Degenerative changes :
 Asteroid hyalosis
 Synchisis schintillans
 Amyloid degeneration

15.  Unilateral
 Old age
 asymptomatic

18.  It affects the damaged eyes which have
suffered from trauma ,VH, inflammatory
diseases in the past.
 Pathognomic feature is crystals settle down
with every pause after stir.
 Golden shower of rain.
 Can occur at any age

19. Amyloid degeneration:
 Amyloidosis is a localised or systemic
condition in which there is extracellular
deposition of fibrillary protein
 Involvement of vitreous occurs in familial
amyloidosis
 Characterised by polyneuropathy ,prominent
corneal nerves and pupillary light near
dissociation.
 Vitreous opacities take a typical GLASS
WOOL appearance.

20.  these get attached to the posterior lens by thick
footplates
 Can lead to severe visual impairment
 Rx : vitrectomy
 RED CELL OPACITIES:
 Cause isVH
 TUMOUR CELL OPACITIES:
 Free floating opacities in patients of RB,
reticulum cell sarcoma and intraocular
lymphomas

21. Vitreous cyst:
 Congenital
 Acquired
 Cause : trauma , inflammation.
 Can be : pigmented : arises from ciliary body
pigment epithelium
 or non pigmented: arise from the remnants of
primary hyaloid vascular system.
 Can be free floating or attached to optic disc
 Rx: laser cystotomy or vitrectomy .

31.  Can present as
 Bergmeister papilla : seen as a tuft at the
optic disc
 Mittendorf dot: seen on the post lens surface

41. Terson syndrome:
 Combination of intraocular and subarachnoid
haemorrhage secondary to aneurysmal
rupture from ant communicating artery.
 Bilateral
 Preretinal or intraretinal haem. Breaks up into
the vitreous
 Rx not required
 Prognosis is usaually good

53.  Anterior vitrectomy: removal of ant.Vitreous
 Core vitrectomy; removal of central bulk of
vitreous
 Subtotal and total vitrectomy:
 TECHNIQUESOFVITRECTOMY:
 Open sky vitrectomy: performed through the
primary wound to manage the disturbed
vitreous in cataract surgery, aphakic
keratoplasty and globe rupture.

54.  Pars plana vitrectomy:
 One port :done with multifunction vitrectomy
probe ( infusion ,suction and cutter(VSC)
 Three port: illumination probe
 Infusion cannula
 Cutter n suction cannula.

55. Vitreous substitutes
 Used in vitreoretinal surgery
 Function :
 To restore IOP
 To provide intraocular tamponade

58.  Silicone oil:
 Benefit is that it allows more controlled
retinal manipulation during vitreoretinal
surgery.

59. Posterior vitreous
detachment:
separation of cortical vitreous from retina
anywhere posterior to vitreous base
Cause : collagen cross linking and selective
loss of retinal adherence are the primary
events.
s/s:
Flashes of light /photopsia occurs because if
mechanical stimulation of retina due to
vitreous traction.

60.  Floaters /cogweb
 Biomicroscopic examination:
 Collapsed vitreous: behind the lens and an
optically clear space between detached
posterior hyaloid face and retina .
 Weiss ring : ring of attachment of vitreos to
optic disc.(pathognomic)

61. Complications:
 Retinal breaks
 VH
 Retinal haem
 RD
 Management:
 Uncomplicated PVD: F/U
 Retinal tear complicating PVD requires LPC
 VH /RD

62.  THANK YOU